By Corky Quirk Special to the Express Summer is right around the corner, and the bats are back! The maternity Mexican free-tailed bat colony under the I-80 Yolo Causeway is growing daily as they return from wherever they spent the winter. Although many of the bats over-winter in the bridge, most seem to leave. As the weather warms, crops grow and insect populations explode, the bats return to the Causeway. These amazing, winged wonders are mammals that can fly. Each summer the females give birth, in late June, to one pup. She nurses that pup for about five to six weeks, and then it joins her as she flies throughout the Central Valley to consume crop pests and mosquitos. There also are males that live in the Yolo Causeway bridge, but their groupings are smaller, so they are less noticeable. Throughout the summer, Yolo Basin Foundation offers many opportunities to learn more about the bats. Registration is now open and some evenings have already sold out. This year the Bat Talk and Walk events are in a hybrid format. The Talk is via Zoom and the Walk is in-person. Maybe you want a more personal experience like Batty for Bats, or to learn to build a Bat House, or possibly you only want to hear the Talk to learn more about bats. All events and some fun fact videos about our programs and the bats can be found at yolobasin.org/bats2021. Yolo Basin Foundation is a nonprofit organization that offers environmental education programs for all ages related to wetlands and wildlife. For more information about their programs and for ways to support their efforts, visit yolobasin.org.